// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/browser/android/app_web_message_port_service_impl.h"

#include "base/android/jni_array.h"
#include "base/android/jni_string.h"
#include "base/bind.h"
#include "content/browser/android/app_web_message_port_message_filter.h"
#include "content/browser/message_port_service.h"
#include "content/browser/renderer_host/render_process_host_impl.h"
#include "content/browser/web_contents/web_contents_impl.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/browser/message_port_provider.h"
#include "jni/AppWebMessagePortService_jni.h"

namespace content {

using base::android::AttachCurrentThread;
using base::android::ConvertJavaStringToUTF16;
using base::android::ConvertUTF16ToJavaString;
using base::android::JavaParamRef;
using base::android::JavaRef;
using base::android::ScopedJavaGlobalRef;
using base::android::ScopedJavaLocalRef;
using base::android::ToJavaIntArray;
using content::BrowserThread;
using content::MessagePortProvider;

AppWebMessagePortServiceImpl* AppWebMessagePortServiceImpl::GetInstance()
{
    return base::Singleton<AppWebMessagePortServiceImpl>::get();
}

AppWebMessagePortServiceImpl::AppWebMessagePortServiceImpl() { }

AppWebMessagePortServiceImpl::~AppWebMessagePortServiceImpl()
{
    JNIEnv* env = AttachCurrentThread();
    ScopedJavaLocalRef<jobject> obj = java_ref_.get(env);
    if (obj.is_null())
        return;
    Java_AppWebMessagePortService_unregisterNativeAppWebMessagePortService(env,
        obj);
}

void AppWebMessagePortServiceImpl::Init(JNIEnv* env, jobject obj)
{
    java_ref_ = JavaObjectWeakGlobalRef(env, obj);
}

void AppWebMessagePortServiceImpl::CreateMessageChannel(
    JNIEnv* env,
    const JavaRef<jobjectArray>& ports,
    WebContents* web_contents)
{
    DCHECK_CURRENTLY_ON(BrowserThread::UI);
    RenderFrameHostImpl* rfh = static_cast<RenderFrameHostImpl*>(web_contents->GetMainFrame());
    int routing_id = web_contents->GetMainFrame()->GetRoutingID();
    scoped_refptr<AppWebMessagePortMessageFilter> filter = rfh->GetAppWebMessagePortMessageFilter(routing_id);

    int* portId1 = new int;
    int* portId2 = new int;
    BrowserThread::PostTaskAndReply(
        BrowserThread::IO, FROM_HERE,
        base::Bind(&AppWebMessagePortServiceImpl::CreateMessageChannelOnIOThread,
            base::Unretained(this), filter, portId1, portId2),
        base::Bind(&AppWebMessagePortServiceImpl::OnMessageChannelCreated,
            base::Unretained(this),
            ScopedJavaGlobalRef<jobjectArray>(ports), base::Owned(portId1),
            base::Owned(portId2)));
}

void AppWebMessagePortServiceImpl::OnConvertedWebToAppMessage(
    int message_port_id,
    const base::ListValue& message,
    const std::vector<int>& sent_message_port_ids)
{
    DCHECK_CURRENTLY_ON(BrowserThread::IO);
    JNIEnv* env = AttachCurrentThread();
    ScopedJavaLocalRef<jobject> jobj = java_ref_.get(env);
    if (jobj.is_null())
        return;

    base::string16 value;
    if (!message.GetString(0, &value)) {
        LOG(WARNING) << "Converting post message to a string failed for port "
                     << message_port_id;
        return;
    }

    if (message.GetSize() != 1) {
        NOTREACHED();
        return;
    }

    // Add the ports to AppWebMessagePortService.
    for (const auto& iter : sent_message_port_ids) {
        AddPort(iter, ports_[message_port_id]);
    }

    ScopedJavaLocalRef<jstring> jmsg = ConvertUTF16ToJavaString(env, value);
    ScopedJavaLocalRef<jintArray> jports = ToJavaIntArray(env, sent_message_port_ids);
    Java_AppWebMessagePortService_onReceivedMessage(env, jobj, message_port_id,
        jmsg, jports);
}

void AppWebMessagePortServiceImpl::OnMessagePortMessageFilterClosing(
    AppWebMessagePortMessageFilter* filter)
{
    DCHECK_CURRENTLY_ON(BrowserThread::IO);
    for (MessagePorts::iterator iter = ports_.begin(); iter != ports_.end();) {
        if (iter->second == filter) {
            iter = ports_.erase(iter);
        } else {
            ++iter;
        }
    }
}

void AppWebMessagePortServiceImpl::PostAppToWebMessage(
    JNIEnv* env,
    const JavaParamRef<jobject>& obj,
    int sender_id,
    const JavaParamRef<jstring>& message,
    const JavaParamRef<jintArray>& sent_ports)
{
    DCHECK_CURRENTLY_ON(BrowserThread::UI);
    base::string16* j_message = new base::string16;
    ConvertJavaStringToUTF16(env, message, j_message);
    std::vector<int>* j_sent_ports = new std::vector<int>;
    if (sent_ports != nullptr)
        base::android::JavaIntArrayToIntVector(env, sent_ports, j_sent_ports);

    BrowserThread::PostTask(
        BrowserThread::IO, FROM_HERE,
        base::Bind(&AppWebMessagePortServiceImpl::PostAppToWebMessageOnIOThread,
            base::Unretained(this), sender_id, base::Owned(j_message),
            base::Owned(j_sent_ports)));
}

// The message port service cannot immediately close the port, because
// it is possible that messages are still queued in the renderer process
// waiting for a conversion. Instead, it sends a special message with
// a flag which indicates that this message port should be closed.
void AppWebMessagePortServiceImpl::ClosePort(JNIEnv* env,
    const JavaParamRef<jobject>& obj,
    int message_port_id)
{
    DCHECK_CURRENTLY_ON(BrowserThread::UI);
    BrowserThread::PostTask(
        BrowserThread::IO, FROM_HERE,
        base::Bind(&AppWebMessagePortServiceImpl::PostClosePortMessage,
            base::Unretained(this), message_port_id));
}

void AppWebMessagePortServiceImpl::ReleaseMessages(
    JNIEnv* env,
    const JavaParamRef<jobject>& obj,
    int message_port_id)
{
    DCHECK_CURRENTLY_ON(BrowserThread::UI);
    BrowserThread::PostTask(
        BrowserThread::IO, FROM_HERE,
        base::Bind(&MessagePortService::ReleaseMessages,
            base::Unretained(MessagePortService::GetInstance()),
            message_port_id));
}

void AppWebMessagePortServiceImpl::RemoveSentPorts(
    const std::vector<int>& sent_ports)
{
    DCHECK_CURRENTLY_ON(BrowserThread::IO);
    // Remove the filters that are associated with the transferred ports
    for (const auto& iter : sent_ports)
        ports_.erase(iter);
}

void AppWebMessagePortServiceImpl::PostAppToWebMessageOnIOThread(
    int sender_id,
    base::string16* message,
    std::vector<int>* sent_ports)
{
    RemoveSentPorts(*sent_ports);
    ports_[sender_id]->SendAppToWebMessage(sender_id, *message, *sent_ports);
}

void AppWebMessagePortServiceImpl::PostClosePortMessage(int message_port_id)
{
    DCHECK_CURRENTLY_ON(BrowserThread::IO);
    ports_[message_port_id]->SendClosePortMessage(message_port_id);
}

void AppWebMessagePortServiceImpl::CleanupPort(int message_port_id)
{
    DCHECK_CURRENTLY_ON(BrowserThread::IO);
    ports_.erase(message_port_id);
}

void AppWebMessagePortServiceImpl::CreateMessageChannelOnIOThread(
    scoped_refptr<AppWebMessagePortMessageFilter> filter,
    int* portId1,
    int* portId2)
{
    *portId1 = 0;
    *portId2 = 0;
    MessagePortService* msp = MessagePortService::GetInstance();
    msp->Create(MSG_ROUTING_NONE, filter.get(), portId1);
    msp->Create(MSG_ROUTING_NONE, filter.get(), portId2);
    // Update the routing number of the message ports to be equal to the message
    // port numbers.
    msp->UpdateMessagePort(*portId1, filter.get(), *portId1);
    msp->UpdateMessagePort(*portId2, filter.get(), *portId2);
    msp->Entangle(*portId1, *portId2);
    msp->Entangle(*portId2, *portId1);

    msp->HoldMessages(*portId1);
    msp->HoldMessages(*portId2);
    AddPort(*portId1, filter.get());
    AddPort(*portId2, filter.get());
}

void AppWebMessagePortServiceImpl::OnMessageChannelCreated(
    const JavaRef<jobjectArray>& ports,
    int* port1,
    int* port2)
{
    DCHECK_CURRENTLY_ON(BrowserThread::UI);
    JNIEnv* env = AttachCurrentThread();
    ScopedJavaLocalRef<jobject> obj = java_ref_.get(env);
    if (obj.is_null())
        return;
    Java_AppWebMessagePortService_onMessageChannelCreated(env, obj, *port1,
        *port2, ports);
}

// Adds a new port to the message port service.
void AppWebMessagePortServiceImpl::AddPort(
    int message_port_id,
    AppWebMessagePortMessageFilter* filter)
{
    DCHECK_CURRENTLY_ON(BrowserThread::IO);
    if (ports_.count(message_port_id)) {
        NOTREACHED();
        return;
    }
    ports_[message_port_id] = filter;
}

bool RegisterAppWebMessagePortService(JNIEnv* env)
{
    return RegisterNativesImpl(env);
}

// static
jlong InitAppWebMessagePortService(JNIEnv* env,
    const JavaParamRef<jobject>& obj)
{
    AppWebMessagePortServiceImpl* service = AppWebMessagePortServiceImpl::GetInstance();
    service->Init(env, obj);
    return reinterpret_cast<intptr_t>(service);
}

} // namespace content
